Refrigeration



Sept. 9, 1941. c. c. coONs 2,255,413

REFRIGERATION Filed Aug. 30, 1937 2 Sheets-Sheet l' INVENTOR 59 Curlzs C. Coonsv ATTORNEY Sept. 9, 1941- c; c. cooNs 2,255,413

REFRIGERATION Filed Aug. 30 1937 2 Sheets-Sheet 2 INVENTOR ATTORNEY Patented Sept. 9, 1941 UNITED STATES PATENT OFFICE REFRIGERATION Curtis 0. Coons, North Canton, Ohio, assignor to The Hoover Company, North Canton, Ohio, a

corporation of Ohio Application August 30, 1937, Serial No. 161,563

49 Claims.

the demand for freezing of ice takes precedence over the demand for box cooling.

It is another object of this invention to provide a refrigerating system which is self-defrosting at all times.

It is another object of this invention to provide a refrigerating systemwhich maintains a high humidity in the storage compartment.

It is a further object of this invention to provide an evaporator having a plurality of sections which are arranged to perform distinct funclions.

It is a further object of this invention to. provide an evaporator having a plurality of sections one of which functions as a box cooler and the other of which functions as an ice freezing coil.

It is another object of this invention to provide a refrigerator wherein melted frost is automatically removed from the box.

It is another object of this invention to provide a refrigerating system having an evaporator composed of a plurality'of-sections which are selectively rendered operative.

Other and further objects of the invention will become apparent as the description proceeds when taken in connection with the accompanying drawings, in which:

Figure 1 is a diagrammatic view illustrating my invention applied to a three-fluid continuous absorption refrigerating apparatus.

Figure} is a sectional view taken along the line 2-2 of Figure 1 and looking in the direction of the arrows.

Figure 3 is a partial sectional view of a detail.

Figure 4 is a view illustrating a modification of the apparatus illustrated in Figure l.

Fi re 5 is a broken view on a smaller scale showing the arrangement of the cooling elements and the water tank in the refrigerator cabinet.

Referring to the drawings and first to Figure l thereof, it will be seen that I have diagram- 6 matically illustrated a continuous three-fluid absorption refrigerating system comprising a.

generator B, an air cooled rectifier R, a finned air cooled condenser C, an evaporator E, and absorber A. These elements are suitably con- 10 nected by various conduits to form a number of gas and liquid circuits and a complete refrigeration circuit.

The generator B comprises an outer liquidretaining vessel II and an inner gas flue I2.

1 The top portion of the space between the vessel I l and the flue l2 forms a gas and liquid separation chamber. Refrigerant vapor, preferably ammonia, is discharged from the vessel ll through a conduit l3 to the rectifier R wherein 2 entrained water vapor is condensed. From the rectifier R the entrained water vapor flows backwardly into the generator B and the refrigerant vapor discharges into an air-cooled condenser C wherein it is liquefied. Liquid refrigerant is discharged from the condenser'C through a conduit ll into the evaporator E through which it flows counter to a stream of an inert gas, such as hydrogen or nitrogen, into which the liquid evaporates to produce refrigeration. The refrigao erant vapor-gas mixture leaves the evaporator through a conduit l5and enters the inner part of a gas heat exchanger l6. From the gas heat exchanger I6, the inert gas refrigerant vapor mixture passes through'a conduit- Il into the bottom of an absorber A. The vapor-gas mixture passes upwardly through the absorber'A in counterflow relation with weak absorption liquid supplied to the top of the absorber A by a conduit l8 connected to the generator 3. The flow 40 through the inert gas system is induced by the density difi'erence'between the column of 'cold rich gas leaving -the evaporator and the column of warm weak gas leaving the absorber. H

--In the absorber A, the refrigerant vapor is absorbed in the absorption solution and the purified inert gas exits from the upper portion of the absorber through a conduit I9 which leads to the outer pass of gas heat exchanger 16. From the outer pass of the gas heat exchanger IS, the

inert gas returns to the evaporator E, through a conduit 20. The conduit 29 is drained to the strong liquor reservoir in the bottom of the absorber A by means of a conduit 2|. The gas return conduit I9 is drained to the conduit 2| by means of a conduit 22.

The strong absorption liquid which collects in the bottom of the absorber A is returned to the generator by way of a conduit 23 which is in heat exchange relation with the weak liquor conduit l8. The conduit 23 is coiled around a lower extension of the flue I2 as indicated at 24. This forms the primary heating portion of the generator due to the fact that the coil 24 is positioned immediately above a gas heating burner 25. Part of the refrigerant contained in the coil 24 is vaporized therein and functions to elevate the weakened liquid through the conduit 28 by the well known vapor lift action. The weak liquor and the refrigerant vapor are discharged into the separation chamber in the upper portion of the space between the flu'e l2 and the vessel II.

The absorber A, which may be of any desired construction, may be cooled in any manner desired. As illustrated, the absorber is cooled by means of a conduit 21 which is coiled therearound and communicates at its upper end with a conduit 28 leading .to an air-cooled bank of finned cooling tubes 29. The cooling tubes 29 communicate with the lower end of the coil 21 bymeans of a conduit 30. The heat absorbed by the coil 21 is transmitted to the fluid therein and a thermo-syphonic circulation occurs through the coil 21, conduit 28, cooling coil 29, and return conduit 30.

.It is to be understood that the gas heat exchanger, absorber, condenser, and boiler are illustrated and described herein onl in a general manner; these elements may partake-of any desired particular construction,

Referring now to the evaporator, it will be seen that it comprises a box cooling coil 3| provided with a series of fins 32, only. one of which is shown. The liquid refrigerant supply conduit I4 and the inert gas vapor mixture discharge of the box cooling coil 3|.

The lower end of the box cooling coil 3| communicates through a conduit 33' with an ice freezing coil. The ice freezing coil, as illustrated, comprises two laterally positioned sections consisting of upper and lower conduits. The near ice freezing section, as viewed in Figure 1, comprises an upper conduit 34 which is connected at its rear end' to the conduit 33 and at its front end to a'lower conduit 35 by means of a return bend. The rear end of the conduit 35 communicates with a transverse conduit 36 which communicates with the rear end of the upper conduit 31 of the remote ice freezing section, as viewed in Figure 1. The conduit 31 communicates at its forward end with a lower conduit 38 which opens into the gas supply conduit previously described. The conduits 33, 34, 35, 36, 31, and 38 are sloped downwardly continuously from the vertical box-cooling coil to the drain conduit 2| in order to permit gravity flow of liquid refrigerant therethrough. The conduits 34 and 35 are suitably secured, as by welding, to a plurality of spaced freezing pads 39, which are preferably constructed from material having a relatively high heat conductivity. The ice freezing evaporatorsectionsfl and38 are connected together by spacedice freezing I conduit I5 both communicate with the upper end pads 40 corresponding to the pads 39 previously described. The pads 39 and 40 are so arranged that they will snugly and slidably receive the tapered bottom plate 4| of a water tank 42. The tank 42 is designed to rest freely upon the pads 39 and 40, whereby it may be removed therefrom simpl by lifting it upwardly or by sliding it forwardly in the refrigerating compartment.

The evaporator is intended to be arranged in the center or near one side of the top portion of a refrigerating cabinet. The box cooling coil 3| is designed to be placed adjacent the rear wall of the cabinet with the ice freezing evaporator sections 34, 35, 31, and 38 projecting forwardly therefrom.

The vessel 42 and the ice freezing portions of the evaporator may be placed in a housing constructed ofinsulating material in order that they may not affect, or be affected by, the condition of the air in the refrigerating compartment. However, it is desirable to expose the contents of the tank 42 for reasons to be described hereinafter.

The control mechanism for the refrigerating system just described will now be explained. The burner 25 is supplied with fuel from a conduit 43. Flow of gas to the conduit 43 is controlled by a solenoid gas valve 44. A pilot burner 46' is supplied with gas by a conduit 45 including a small regulating valve 46. Any suitable means may be provided to stop the flow of gas in the event of complete flame failure at the generator B.

The box cooling coil 3| is completely enclosed in a box 41 of insulating material. The upper and lower ends of the box "are closed by movable fiap valves 48 and 49, respectively. The flap valve 49 is pivoted upon a suitable support at 50. The flap valve 49 is pivoted upon a suitable support at 5|. The flap valves 48 and 49 are connected together by means of a rod 52 which is pivoted at 53 to the flap valve 48 on the right hand side of the pivot as viewed in Figure 1, and is pivoted at 54 on the left hand side of the pivot 5| of the flap valve 49, as viewed in Figure 1. The flap valve 49 is provided with a rear extension, as viewed in Figure 1, which is pivotally connected at; 55 to a vertically extending actuating rod 56. The arrangement is such that upward movement of the rod 56 causes both flap valves to pivot about their respective pivots in opposite directions and thereby open the upper and lower ends of the box 41 whereby the air contained in the refrigerating compartment may freely circulate therethrough and over the box cooling coil 3| and the fins 32. It will be seen that the flap valves move in opposite directions whereby they are mutually counterbalanced and require a minimum of power to be operated.

The upper end of the actuating rod 56 slidably receives an insulating collar 56 which is rigidly mounted on a bimetallic thermostatic switch arm 51. The thermostat 51 is positioned to be responsive to the temperature of the air in the refrigerating compartment. A small cushioning spring 58 is interposed between the insulating collar 56' and an enlarged head 59 on the extreme upper end of the actuating rod 56. The bimetallic thermostat 51 is the box temperature control switch for the apparatus and will be described more fully hereinafter.

An ice-freezing control is also provided and operates inconjunction with the box cooling control'previously described. The ice-freezing con-, trol comprises a bimetallic'thermostat 50 which hereinafter.

those portions of the water tank 42 in direct conis mounted in thermal contact with one of the ice-freezing pads 39, or 49, or in thermal contact with the water vessel 42 closely adjacent to an ice-freezing pad.

Power is supplied to the control mechanism from a line wire 6| directly to a U-shaped electrical contact 60 which is mounted on and insulated from the bimetallic element lill.v The bimetallic element 69, which is responsive to the demand for refrigeration at the ice-freezing portion of the evaporator, is positioned to cause the member 60 to contact an electrical contact 62 when a block of ice has formed on the inside of the water tank 42. This will occur at a relatively low temperature such as, for example, or degrees Fahrenheit. The contact 62 is connected by means of a wire 63 to the thermostatic switch 51. The box temperature responsive thermostat 51 is adapted to close the circuit through an electrical contact 64' which is connected by means of a wire 65 to a wire 66 leading to the solenoid valve 44. The wire 66 is also connected to a contact 61 which is positioned to be contacted by the contact 60 on the thermostatic element 66 under conditions to be described The solenoid gas valve 44 is connected by means of a wire 68 to a solenoid coil 69 which is positioned to attract a magnetic armature 56" carried by the lower end of the actuating arm 56. The solenoid coil 69 is connected by means of a wire 10 to a contact 1| which is positioned to be contacted by the contact 68' simultaneously with the contact 61. The wire 68 is also connected to the line wire 12.

The operation of this form of the invention will now be described. Assuming that the machine has been out of operation and that. the air temperature in the boxand the temperature of the ice-freezing portion of the evaporator aresuch as to create a demand for refrigeration, the thermostat 51 will be flexed upwardly whereby to open the flap valves 49 and 48 in order that the air within the box may have its temperature lowered by contact with the box coling coil 3|. However, under these conditions the thermostatic element 60 has shifted to the left as viewed in Figure 1 and is closing the circuit through the contacts 61 and 1 I. The current then flows from the line 6| through the contact 66', the contact 1|, the wire 19, the solenoid coil 69, the wire 68 and back to the line wire 12. Current also flows from the switch contact 60' through the contact 61, the wire 66, to the solenoid valve 44 and from,

the solenoid valve 44 through the wire 68 to the line wire 12. Energization of the solenoid coil69 tact with the freezing pads 39 and 40.

Ice freezing continues until the ice blocks formed within the tank 42 have reached such thickness that the heat transfer therethrough to the pads 39, or 40, has reached such a low value that the temperature of the ice-freezing coils of the evaporator reaches a very low value.

When the temperature of the ice-freezing coils of the evaporator has reached a very low value the thermostat 68 flexes to the right, as viewed in Figure 1, thereby de-energizing the solenoid coil 69 and the solenoid valve 44.

When the ice blocks have formed on the icefreezing coils and the thermostat 66 has moved to the right, as viewed in Figure 1, the contact 69' contacts the electrical contact 62. Current now flows from the line 6| through the contact 60',

contact 62, wire 63, bimetallic thermostatic switch element 51, contact 64, wire 65, wire 66, to the solenoid valve 44. Current flows through the solenoid valve 44 through the wire 68, and line wire 12 as before. It will be-seen that under these conditions the solenoid coil 69 is de-energized and the bimetallic switch element 51 is flexed upwardly to cause the actuating rod 56 to open the flap valves 46 and 49. The air in the refrigerating compartment is now able to reach the box-cooling coil with the result that the temperature of the coil is very rapidly raised and the refrigerant liquid supplied thereto from the conduit l4, instead of simply passing into the icefreezing coils, evaporates into the inert gas flowing upwardly through the box-cooling coils and produces refrigeration therein. Due to the fact that refrigerant liquid is no longer supplied to the ice-freezing coils of the evaporator the ice blo'cks formed adjacent the freezing parts 39 and 40 melt free from the metal surfaces of the vessel 42 and float to the surface of the water therein contained. Melting of the ice blocks is accelerovercomes the tension of the bimetallic thermov stat 51 against the cushion spring 58 and pulls the actuating rod 56 downwardly to effect closure of the flap valves 48 and 49. Energization of the solenoid valve 44 causes a flame to be carried on the burner 25. As a result of this action, refrigerant liquid is discharged from the conduit i4 into the evaporator box-cooling coil 3|. Due to the fact that the box-cooling coil is completely enclosed in the insulating casing 41 and the flap valves 48 and 49 are closed, no refrigeration can take place in this coil except a small amount necessary to lower the temperature to such a point that the refrigerant liquid will no longer evaporate into the inert gas. After lowering the temperature of the box-cooling coil, the refrigerant liquid discharges into the inlet 33 of the icefreezing coils of the evaporator. Refrigeration then takes place in the coils 34, 35, 36, 31 and 38 whereby ice is frozen on the inner surface of ated due to the fact that the freezing pads, icefreezing coils, and water .tank are in direct contact withthe air in the food compartment.

The box-cooling coil continues to produce refrigeration until the temperature of the air within the box has reached the value for which the thermostat 51 'is set whereupon the thermostat 51 flexes downwardly, as viewed in Figure 1, and

causes the actuating rod 56 to close the fiapvalves 48 and 49. If the iceblocks should melt free before the box-cooling coil has reduced the temperature of the air in the refrigerator to the value for which the thermostat 51 is set, the thermostat 66 will shift to the left, as viewed in Figure 1, and energize the solenoid valve and the'solenoid coil 69 in the manner previously described thereby producing refrigeration in the ice-freezing coils and causing closure of the flap valves 48 and 49 irrespective of the positionof thermostat 51.

Thus it will be seen that I have provided a refrigeration control mechanism so arranged that the demand for ice takes precedence over demand for box cooling and in which a control responsive to demand for ice and another control responsive to demand for refrigeration in the food preserving portions of the vbox'are properly interrelated toachieve the desired results.

It is believed that the following table will make the operation of my control. apparatus perfectly clear. In this table column A represents the temperature of the ice-freezing pads 39 and 40.

the contacts 61 and H are made when the icefreezing pads reach a temperature of 33 degrees Fahrenheit. Also for purpose of illustration, it is assumed that the thermostat 51 makes the contact 64 when the temperature of the air and the box reaches 45 degrees or exceeds that figure. Column B represents box temperature. Column indicates the electrical contacts made by the switch contact 60'. Column D indicates whether or not the circuit is closed through the'contact 2,255,413 temperature of 25 degrees Fahrenheit and that I the insulation in the back wall of the refrigerating compartment and-the conduits I5, 20, 14, and I4 pass through the rear wall of the refrigerating compartment. It will be understood that the present disclosure is diagrammatic and that the thermostatic control mechanism and the actuating mechanism will be arranged in the refrigerator to be hidden from view.

64. Column E indicates the condition of the flap valves 48 and 49. Column F indicates the condition of the solenoid gas valve 44. Column G represents the condition of the solenoid coil 69.

A B O D E F G 33 45 Open Closed. Open.-- Energized. 25 45 62 Closed. 0pen. do. De-energized. 33 45 0peu Closed. -do Energized.

25 45 62 do do Closed. Deenergized.

It is believed that the above table clearly indicates the control exercised by the two controlling switches. It is to be noted that demand for ice takes precedence over demand for box-cooling at all times.

The above described control mechanism is selfdefrosting; that is, the frost which forms on the ice-freezing portions of the evaporator automatically melts therefrom during the period when these portions of the evaporator are inoperative in order to release the ice blocks frozen inside the vessel 42. A minute amount of frost may form upon the box cooling coil during the time when the flap valves 40 and 49 are closed due to the slight amount of moisture contained in the air entrapped within the insulating box 41. However, this frost will melt as soon as the machine operates to cool the box, and at this time there will be no frost deposition on the coil 3| or fins 32 due to the fact that their temperature is not sufiiciently low to freeze moisture from the air. It. will be seen that there is a continuous formation of frost and a melting thereof; therefore some means must be provided to eliminate this moisture continuously and automatically.

I have illustrated one means of disposing of the frost drainage in Figure 3. The drainage system includes a pan 13 which is positioned entirely beneath the box cooling and ice freezing Any drippage from portions of the evaporator. any portion ofthe evaporator is caught in the pan 13 and is discharged through a conduit 14 to the chimney I2 of the boiler B. That portion of the chimney I2 which extends abovethe shell II is provided interiorly thereof with a coiled wire 15 which is positioned to intercept liquid draining through the conduit 14. The wire coil 15 causes the drainage to spread over the large area of the coil and to be evaporated rapidly by the exhaust gases from the burner 25. The pilot flame carried on theburner 46' is sufiicient to evaporate any drainage occurring at this time.

It will be understood that the disclosure in Figure 1 is diagrammatic. Preferably the apparatus will be applied: to an insulated refrigerating cabinet with the boiler, absorber, absorber cooler, and condenser positioned beneath the refrigerating compartment or rearwardly thereof. The heat exchanger is preferably imbedded in Referring now to Figure 4 there is disclosed a modification of the control apparatus illustrated in Figure 1. It will be understood that the refrigerating system, with the exception of the control mechanism now to be described, may be identical with that disclosed in connection with Figure 1. parison, the evaporator box-cooling coil, the

v freezing coil, the freezing pads, the water vessel.

the box-cooling coil casing, the flap valves, and the connecting linkage for the fiap valves will be provided with the reference characters utilized for identical parts in Figure 1.

A short actuating arm 58 is connected at one end to aresilient operating arm IOI of a mag-- netic toggle mechanism I09 and is pivotally connected at its opposite end at 55 to an extension of the flap valve 49 which is connected with the fiap valve 40 by a link 52 in a manner previously described whereby the flap valves are operated Y simultaneously.

This form of the inventionfis designed to freeze ice blocks within a containing vessel 42 in the same manner in which the invention of Figure 1 operates. Only the evaporator sections 04 and 35 are illustrated in Figure 4 though it will be understood that the evaporator is identical with that disclosed in Figure 1. The icefreezing pads 39 are identical with those disclosed in Figure 1'.

Gas is supplied to a gas burner similar to that disclosed in connection with Figure 1 from a conduit I02, an on and oil. valve I03, and a conduit I04. The valve I 03 is provided with a slotted actuating arm I05 which receives a pin I06 mounted on the end of a resilient actuatingtion. and will contact a resilient switch contact II! when the gas valve I03 is in the closed'position. The switch contact U2 is connected by means of a wire I I4 to the solenoid coilI I5 which in turn is connected by means of a wire Hi to aswitch contact H1. The switch contact II! is connected by a wire 0 to a solenoid coil- II! which is connected by means of 'a wire I20 to a contact I2I and to a contact" I22. It will be noted that the switch contacts H2 and III are positioned to energize solenoid coils, which will urge the arm I01 in a direction to break the circuit through the switch contact in engagement with the arm I01. The resilient switch contacts are positioned to maintain the circuit until the For purposes of convenient com- It will be understood that any suitable I01 and insulated therefrom by any suitable means not shown.

The contacts II1 contacted by a bimetallic thermostatic switch blade I23 which is connected by a wire I24 to a contact I25. The bimetallic member I23 is positioned to be responsive to the temperature of the air in the box and corresponds to the thermostat 51 previously described.

When the temperature of the box exceeds a given predetermined value,-45 degrees for example, the circuit is made through the contact I2I. When the temperature of the box drops below the predetermined temperature the circuit is made through the contact H1. The operation of this switch in conjunction with the remainder of the control apparatus will be more fully described hereinafter.

Power is also supplied through the line I41 to a U -shaped contact I3I which is mounted in insulating material I32 carried on the free end of a.

bimetallic thermostat I29. The bimetallic thermostat I29 is rigidly mounted on a block I30 of material having a high heat conductivity and in good thermal contact with the ice-freezing evaporator coils 34 and 35 whereby the'bimetallic thermostat I29 responds to temperature conditions of the ice-freezing coils. In the right hand position of the thermostat I29, as viewed in Figure 4, the contact I3I engages the contact I22,

previously described, and a contact element I33.

In the left hand position of the thermostat I29, as viewed in Figure 4, the contact I3I engages the switch contact I25, previously described, and

a switch contact '34. The contact I33 is con-' nected by a wire I35 to a solenoid coil I36 which is connected by wire I31 to a resilient switch contact I38. The switch contact I34 is connected by a wire I39 to a solenoid coil I40 which is connected by a wire I4I to a resilient switch contact I42. The actuating toggle arm IN is connected by a wire I43 to the line wire I I0.

and I2I are adapted to beis warm, it will alsobe assumed that the gas valve is closed and that the flap valves 48 and 49 are open. The thermostatic element I29 will then be moved to the right, as viewed in Figure 4, and will make contact with switch contacts I22 and I33. The bimetallic element I23 will be" flexed upwardly to close the circuit through contact I2I,

as viewed in Figure 4. As a tions power will be supplied from the line IIO to the magnetic toggle arm I01, contact II3, wire II8,-solenoid coil II9, wire I20, contact I22, and contact I3I to the line I41. This will energize the gas valve controlling magnetic toggle in such'fashion that the gas valve is moved to the open position and the circuit is broken at the contact 3. Power will be supplied from the line I I0 through the wire I43, the magnetic toggle arm IOI, contact I38, wire I31, solenoid coil I36, wire I35, contact I33, and contact I3I to the line I41. This action will shift the magnetic toggle mechanism IOI into position to close the. flap valves 48 and 49. even though the bimetallic element I23 be in a position to demand refrigeration for the box.

I The condition just described will continue until a sufllcient quantity of 'ice has formed on the inside wall of the vessel 42 whereupon the bi metallic element I29 will flex to the left, as viewed in Figure 4, and will close the circuit through contacts I34 and I25. If the arm I23 isstill in a position to demand refrigeration for the air within the refrigerator box, the gas valve will remain in the position to which it was initially urged. Assuming a demand for refrigeration for the air in the'box, power will be supplied through the line IIO, the wire I43, the arm II", the contact I42, the wire I4I, the solenoid coil I40, wire I39, contact I34 and contact I3I to the line I41. This will shift the magnetic toggle arm IOI upwardly as viewed in Figure 1 with the result that the flap valves 48 and 49 will be open to permit the air in the box to The free end of the toggle arm II is provided with a pin I52 which is engaged in the end slot of a toggle arm I53 which is pivotally mounted at I54 on a. suitable fixed support. A toggle spring I55 is connected at its ends to a fixed supcirculate freely over the box cooling coil 3| and the fins 32, and the circuit will be broken by disengaging the contact I42 and the arm IOI after the toggle has snapped over center.

port- I56 and to the free end of the toggle arm I53.

The solenoid coils I36 and I40 are provided with iron cores I44and I45, respectively. These iron cores are adapted to attract a soft iron armature I46 which is suitably mounted in the arm WI and suitably insulated therefrom by means not shown. f

The resilient contacts I38 and I42 are arranged to maintain contact with the actuating arm IOI until it has moved the spring I55 past the pivot point of the arm I53. Each-of the contacts I38. and I42 is connected to a solenoid coil which operates to urge the actuating arm in a direction to break the circuit between the contact and the' arm IOI. For example, if the arm IOI'isin en-' gagement with the contact I42, energization of the wires I39 and I43 will cause energization of the solenoid coil I40 through the contact I42 and the arm IOI. Under these conditions the arm IOI will be snapped'upwardly, as viewed in Figure 4, and will deenergize thecoil I40 by breaking the contact between I42 and IN.

The operation of this form of the invention will now be described. .Assuming that the machine is entirely out of operation andthat the box temperature exceeds the temperature for which the thermostat I23 is set, for example, degrees, and that the water within the tank 42 The condition just described will continue until such time as the box temperature shall have reached the predetermined value whereupon the bimetallic thermostat I23 will flex downwardly, as viewed in Figure 4, and close the circuit through the contact 1. Power will now be supplied through the line IIO, toggle arm I01,

contact I I2, wire II4, solenoid coil II5, wire II6, contact I", bimetallic element I23, wire I24, contact I25, andcontact m to the line m. I If the ice blocks should entirely free themselves before the box temperature reaches the value for which the thermostat I23 is set, the thermostat I29 willshift to the right, as viewed in Fig. 4, and cause closure of the flap valves 48 and 49 regardless of the position of the thermostat I23 It is believed that the following table will make clear the operation of this form of the invention. In this table column A represents the temperature of the ice freezing coils. For purposes of illustration it is assumed that the contacts I22 and I33 are made when the temperature reaches 33 F. and that the contacts I25 and I34 are made when the temperature reaches 25 F. Column B represents the temperature of the air in the box. For purposes of illustration it is assumed that the contact I2I is made when the temperature exceeds 45 F. and that the conresult of these condi- The frost drainage collecting the box it acts as cilitates tact I I 'l is made when the temperature falls below 45 F. Column C indicates the contacts made' by the contact I3 I Column D indicates the contacts made by the thermostat I23. Column E indicates the condition of the flap valves 48 and 49. Column F indicates the condition of the gas It will be noted that in this form of the invention power is utilized only to shift the various valves from one position to another; there is no continuous consumption of electrical energy.

Figure 5 illustrates the arrangement of the freezing elements in the cabinet. The controls, conduits, and other parts of the system are omitted for clarity. It will be noted that the water tank 42 conceals the insulating box 41 and that it may be slid forwardly on the freezing pads for removal from the cabinet 200.

A few advantages and useful functions which naturally flow from both forms of the invention described are worthy of note. Due to the fact that the water in .the tank 42 is constantly exposed to circulating air in the refrigerating compartment the humidity of the air within the compartment is maintained at a relatively high value. If desired the water tank 42 can be provided with a cover to prevent contamination of the contents of the vessel and to reduce heat loss therefrom.

This does not impair the humidifying properties of the water tank as the cover will not be sealed.

in the pan 13 is a' further factor in maintaining a high humidity within the refrigerating compartment.

By reason of the fact that the individual blocks of ice float freely in a body of very cold water, the housewife'need not take out a large number of ice cubes at one time; any number of cubes, from one to the maximum capacity of the unit, maybe ladled out of the water tank42 .as desired. This arrangement of the formation of ice cubes eliminates the necessity for trays, grids, and special ice cube releasing mechanisms.

The water .tank 42 may be spigot I15 whereby fresh cold drinking water is available at all times.

When the water tank is exposed tothe air in a thermal flywheel due to its large heat capacity. That is, the large body of coldwater and ice in the tank prevents excessive temperature changes in the air in the box.

By reason of the readily removable mounting of the vessel 42 upon the ice-freezing evaporator coils, it is a very simple matter to remove this element to facilitate cleaning of the vessel 42, or other parts of the refrigerating compartment. The ready removability of the vessel 42 also fathe process of adding water thereto. For example, when it is desired to add water to-the vessel 42, it may he 'slid forwardly on the icefreezing coils without'being removed therefrom until the forward end of the vessel 42 projects provided with a outwardly of the refrigerating compartment. In.

this position it is a very simple matter to pour water into the vessel 42 from a kettle or other suitable carrier. The ice-freezing coils may be made deep enough to prevent the vessel 42 from over-balancing when pulled outwardly beyond the front opening of the refrigerating compartment.

A door 21H is shown in the top portion of the refrigerating cabinet. This provides an alternate'means of supplying water to the tank 42 and of removing ice blocks from the tank. The top door has the advantage that it is not necessary to -open the storage compartment door in order to obtain access to the freezing tank. Also the door 2M does not permit the cold air in the box to escape when ice is removed from the freezing tank.

While I have described several embodiments of my invention, it is to be understood that the invention is capable of embodiment in other constructional forms without departing from the invention or the scope of the appended claims.

I claim:

1. A refrigerating system including an evaporator having distinct box-cooling and ice-freezing sections, said sections being arranged so that liquid refrigerant supplied to the top portion of the box-cooling section may flow downwardly through the entire evaporator by gravity, means for supplying an inert gas stream to the lowest portion of the evaporator, and means responsive to demands for refrigeration operative to cause evaporation of the liquid refrigerant into the inert gas stream to occur in a selected one of said sections.-

2. A refrigerating system including an evaporator, means for supplying liquid refrigerant to said evaporator, means for supplying a pressure equalizing medium to said evaporator, and means operative to cause substantially all the liquid refrigerant to evaporate into the pressure equalizing medium in a selected section of said evaporator.

3. A refrigerating system including an evaporator having a vertically positioned box-cooling coil and an ice-freezing coil positioned therebelow, a cas enclosing said box-cooling coil, valves in said casing arranged to permit or to prevent flow of air therethrough, and means operative to open fgid valves in response to a demand for box-cool- 4. That improvement in the art of absorption refrigeration which includes the steps of conducting a stream of pressure equalizing medium through a-path in heat exchange relation with material to be frozen and then through a path in heat exchange relation with a fluid to be cooled, supplying refrigerant to be. evaporated to said path, and controlling the area of evaporation in such manner that substantially all the evaporation occurs in one path or the other.

5. An evaporator for refrigerating systems comprising a vertically positioned coil provided with fins, a pair of spaced horizontally positioned, reversely bent, series and connected to said vertically positioned coil, andaplurality offreezingpadsmounted upon said horizontal coil sections whereby they are adapted to receive a vessel containing water to be frozen.

-6. A refrigerating system comprising a boiler,

-a condenser, an evaporator, and an absorber connected in circuit to provide a continuous absorption refrigerating system, a water tank positioned in heat exchange relationship with said coil sections connected.together in period of time to form an ice block within said water container and to thereafter render said pressure equalizing medium in order to produce refrigeration characterized by the fact that the said evaporation occurs in a zone in. heat exchange relationship at a plurality of points with a large body of water whereby a plurality of blocks of ice are formed in said body of water,

continuing evaporation until blocks of a predetermined size have been formed, discontinuing evaporation in heat exchange relationship with said plurality of points and producing evaporation in a zone in heat exchange relationship with a medium to be cooled.

8. Refrigerating apparatus comprising a generator, a gas burner positioned toheat the generator, a solenoid valve controlling said gas burner, a condenser, an evaporator comprising separate box-cooling and ice-freezing sections, an insulating box provided with a pair of flap valves enclosing said box-cooling section, a thermostatic mechanism adapted to move said flap valves to open and closed position, means whereby said thermostatic mechanism energizes said solenoid valve when it moves said flap valves to open position, thermostatic mechanism responsive to refrigeration demandby said ice freezing section,

means whereby said second mentioned thermo- 5 static mechanism is operative to energize said solenoid valve, and means energized simultaneously with the solenoid valve by said second thermostatic mechanism operative to force said flap-valves to closed position irrespective of the position of said first mentioned thermostat.

9. Refrigerating apparatus including means controlling the supply of energy thereto, an evaporator having box cooling and ice freezing sections, means constructed and arranged to-allow or prevent flow of air over said box cooling section, magnetic means for controlling said air fiow' control means, magnetic means for controlling said energy supply control means, means responsive to box temperature operative to energize said second mentioned magnetic means to permit or to prevent energy supply in accordance with the demand for box cooling, and means for energizing said magnetic means to prevent air fiow over said box cooling coil and to supply energy in response to a demand for ice freezing and operative to energize said first mentioned magnetic means to allow air flow over said boxcooling coil whenever there is no demand for ice freezing.

10. An absorption refrigerating system com- 6 prising an evaporator having a plurality of sections-means for supplying refrigerant liquid and a pressure equalizing medium to said evaporator.

means adapted to isolate one section of said evaporator thermally to prevent evaporation of refrigerant therein, means responsive to a condition produced by another section of said evaporator for controlling said refrigerant supply means and said isolating means, and means responsive to a condition produced by said one section of said evaporator for controlling'said isolating means and said refrigerant supply means when said first mentioned condition responsive means has operated in a predetermined manner. 7

11. A refrigerating system including an evaporator having distinct box-cooling and ice-freezing sections, said sections being arranged so that liquid refrigerant supplied to the top portion of the box-cooling section may flow downwardly through the entire evaporator by gravity, means for supplying an inert gas stream to the lowest portion of the evaporator, and thermostatically actuated control means responsive to refrigeration demand for forcing the refrigerant to eviaporate in a selected section of said evaporator and for subordinating the refrigerating requirements of one of said sections to the refrigerating requirements of another of said sections.

12. That improvement in the. art of absorption refrigeration which includes the steps of conducting a stream of pressure equalizing medium through a path in heat exchange relation with material to be frozen and then through a path in heat exchange relation with a fluid to be cooled, supplying refrigerant to be evaporatedto said path, evaporating substantially all the refrigerant in whichever one of said paths is in heat exchange relation with material requiring refrigeration, and producing refrigeration in a selected one of said paths whenever there is a demand therefor without regard to the refrigerating requirements of the other of said paths.

13. A refrigerating system including an evaporator having a vertically positioned box-cooling coil and an ice-freezingcoil positioned therebelow, a casing enclosing said box-cooling coil, valves in said casing arranged to-permit or to prevent flow of air therethrough, means operative to open said valves in response to a demand for box-cooling, and means for preventing operation of said flap valves when there is a de-' mand for refrigeration in said ice-freezing coil.

14. Refrigerating apparatus including an evaporator having a plurality of serially connected sections, means for supplying refrigerant liquid and a pressure equalizing medium to said evaporator, means responsive to a first condition for rendering said supply means operative and for substantially preventing evaporation of refrigerant into the pressure equalizing medium in one section of said evaporator, means responsive to a second condition for rendering said supply. means operative and for conditioning said one section to allow evaporation of refrigerant therein provided said section is not rendered inoperative by said first mentioned condition responsive means. i

15. A refrigerating system comprising a boiler, a condenser, an evaporator, and an absorber connected in circuit to provide a, continuous absorption refrigerating system, a water tank positioned in heat exchange relationship with a portion of said evaporator, and means for causing evaporation to occur within said portion of sald evaporator for a sufiicient period of time to form an ice block within said water container and to thereafter render said portioniof said evaporator inoperative for a period of time sufficient to permit said 'ice block to melt free of the wall of said container, and means for causing evaporation to occur within another portion of said evaporator during the ice melting period if there is a demand therefor.

16. Refrigerating apparatus including a plurality of. evapor'ators, an absorber, means for supplying liquid refrigerant to said evaporators, means forming a pressure equalizing medium circuit including said absorber and said evaporate",

said pressure equalizing medium circuit being constructed and arranged to cause circulation of said pressure equalizing medium by factors wholly within the system, and temperature responsive means for causing substantially all of said liquid refrigerant to evaporate into said pressure equalizing medium in a selected one of said evaporators.

17. A refrigerating system including a generatcr, a heater for said generator, a heat discharge flue for said heater, an evaporator, control means constructed and arranged to cause said evaporator to operate at temperatures above and below the melting point of ice, means positioned to collect the drainage from frost melting from said evaporator,-and means for conducting said drainage into said exhaust flue.

18. A refrigerating system including a generator, a heater for said generator, a heat discharge flue for said heater, an evaporator, control means constructed and arranged to cause said evaporator to operate at temperatures above and below the melting point of ice, means positioned to collect the drainage from frost melting from said evaporator, means for conducting said drainage into said exhaust flue, and means within said flue constructed and arranged to spread said drainage in a thin film over an ext-endedsurface area.

19. Refrigerating apparatus comprising an evaporator having distinct box-cooling and icefreezing sections, a water container in heat transfer relationship with said ice-freezing section at a plurality of spaced points'whereby a plurality of separated blocks of ice are formed on the inner wall of said container whenever said ice-freezingevaporator section is operative, and control means operative to cause evaporation to occur within said ice-freezing evaporator section for a period of time'suflicient to produce blocks of ice of a predetermined dimension within said water compartment and to render said ice-freezing evaporator section inoperative thereafter for a period of time sufficient to permit said ice blocks to melt free of-the inner wall of said water vessel and to float to the surface of the water contained therein, said control means also being operative to allow substantial evaporation to occur within said box-cooling coil only during those times when there is no demand for evaporation to produce ice and there is a demand for box cooling.

20. A refrigerating system including an evaporator having'distinct box-cooling and ice-freezing sections, means for supplying energy to said system, means responsive to ,box temperature adapted to render said box-cooling element operative or inoperative in accordance with the demand for box cooling and to render said energy supply means operative, means responsive to the demand for ice freezing, and adapted to render said energy supply -means operative or inoperative and to render said box cooling c'oil inoperative regardless of the demand for box cooling whenever said last mentioned means has rendered said energy supply means operative.

21. Refrigeration apparatus comprising an evaporator having'separate box-cooling and icefreezing sections, an insulating box enclosing said box-cooling section, a pair of flap valves pivotally mounted on opposite ends of said box to control flow of air over said box-cooling coil, a thermostat positioned to be responsive to the temperature of the air in the box and adapted .to move said flap valve to open or closed position,

a thermostat responsive to the demand for icefreezing and adapted to condition the system to produce refrigeration, and means energized by said ice demand thermostat operative to close said flap valve.

22. Refrigerating apparatus including means controlling the supply of energy thereto, an evaporator including box-cooling and ice-freezing sections, an insulating casing enclosing said box-cooling section, valve means mounted on said insulating casing adapted to allow or prevent fiow of air over said box-cooling section, a reciprocably mounted arm connected to cause opening or closing of said valve means, a thermostat positioned to be responsive to the temperature of the air in the box for operating said reciprocably mounted arm, a circuit closed by said thermostat when it has moved said valve means to open position and to operate said energy supply control means to energy supply position; a thermostat mounted to be responsive to the temperature of said ice-freezing section,

' a circuit closed by said second mentioned thermostat in response todemand for ice-freezing operative to condition said energy supply control means to supply energy to the refrigerating apparatus and including a solenoid coil sur-' rounding said reciprocating arm and operative to cause closure of said valve means when energize'd independently of the condition of said first mentioned thermostat.

23. Refrigerating apparatus comprising means controlling the supply of energy thereto, an

supply of energy to the apparatus, and operative in another position to cause opening of said airflow control means, .and means responsive to the temperature of the air in the box operative in one position to energize said second mentioned magneticmeans to supply energy to said system and operative in another position to energize said second mentioned magnetic means to discontinue supply of energy to said system.

24. Refrigerating apparatus comprising an evaporator constructed and arranged to support a large tank containing water, and means operative to cause refrigeration to occur in said evaporator for a sufficient period of time to freeze ice blocks on the interior of those portions of said water tank in contact with said evaporator and further operative to prevent refrigeration in said evaporator for suflicient periods of time to permit said ice blocks to melt free of the side wall of said tank and to float to the surface of the water thereincontained, a second evaporator, and means for rendering said second evaporator operative to cool air when said first-mentionedevaporator is inoperative.

prising a solution circuit including a to allow the inert gas to flow therethroug h, said 1 mands for refrigeration, means for collecting melted frost dripping from said evaporator, and means for conducting said drainage to said flue whereby it is evaporated either by said main burner or by said pilot burner depending upon whether or not said main burner is operating.

26. Refrigerating apparatus comprising an evaporator having a vertically positioned boxcooling coil and a horizontally positioned icefreezing coil extending laterally from the lower portion of said box-cooling coil, freezing pads on said ice-freezing coil, a water tank constructed and arranged to be mounted upon said freezing pads in such manner that it substantially conceals said box-cooling coil and may be removed from said ice-freezing coil by being lifted upwardly therefrom or slid forwardly thereof.

2'7. Refrigerating apparatus comprising a refrigerating compartment, a finned coil positioned in said compartment to be swept by air current therein, an open ended box of insulating material surrounding said coil, a pair of flap valves on opposite ends of said box positioned to open in opposite directions, means connecting said flap valves for simultaneous movement in opposite directions whereby they are counterbalanced, and means responsive to box temperature operative to open and close said flap valves.

23. Refrigerating apparatus including an evaporator having distinct box-cooling and ice-freezing evaporator sections, means operative to allow or to prevent flown of air over said box-cooling section, and means responsive to air temperature operative to control said air-flow control means.

29. Absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit including an evaporator and said absorber, means for supplying refrigerant vapor produced in said boiler to said evaporator in liquid phase, and control means for selectively restricting the production of refrigeration to a portion of said evaporator.

30. Absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit including an evaporator and said absorber, means for supplying refrigerant vapor produced in said boiler to said evaporator in liquid phase, and control means for selectively restricting the production of refrigeration to any one of a plurality of portions of said evaporator which is subject to a refrigeration demand, said control means being arranged to confine the refrigerating effect to a selected one of said portions of said evaporator whenever there is a demand therefor to the exclusion of refrigerating demands from other portions thereof.

31. Absorption refrigerating apparatus comboiler and an absorber, an inert gas circuit including an evaporator and said absorber, means for supplying refrigerant vapor produced in said boiler to said evaporator in liquid phase, means for substantially preventing or allowing the absorption of heat by one portion of said evaporator and control means for operating said heat absorption regulating means in accordance with the demand for refrigeration.

32. Absorption refrigerating apparatus comprising a solution circuit including a boiler and an absorber, an inert gas circuit including an evaporator and said absorber, means for supplying refrigerant vapor produced in said boiler to said evaporator in liquid phase, said evaporator comprising a plurality of sections all. connected sections being arranged for serial flow of the refrigerant liquid therethrough, means adapted to allow or prevent material absorption of heat by selected portions of said evaporator and refrigeration demand responsive means for controlling said heat absorption allowing or preventing means.

33. Refrigerating apparatus including an insulated storage compartment, a cooling unit having a plurality of sections within said insulated compartment, means for supplying a cooling medium to said cooling unit, means adapted to prevent substantial absorption of heat by one of said sections of said cooling unit, and refrigeration demand responsive means for operating said heat absorption preventing means.

34. Refrigerating apparatus including an insulated storage compartment, a cooling unit having a plurality of sections within said insulated compartment, means for supplying a cooling medium to said cooling unit, means adapted to prevent substantial absorption of heat by one of said sections of said cooling unit, refrigeration demand responsive means for operating said heat absorption preventing means, said refrigeration demand responsive means being constructed and arranged to place said heat absorption preventing means in-heat absorption preventing condition whenever there is a demand for refrigeration by the section of said evaporator not directly affected thereby.

35. In a refrigerating apparatus, a cabinet structure including an insulated storage chamher, a cooling unit positioned in said storage chamber, said cooling unit including a plurality of sections, means for supplying a refrigerant liquid to said cooling unit, means for supplying an inert gas to said cooling unit, and means for controlling the temperatures of said sections of said cooling unit including means operative to inhibit and promote absorption of heat by one of said sections whereby the temperature of another of said sections rises when absorption of heat and evaporation of the liquid refrigerant by said one section of said cooling unit is promoted and the temperature of said another section of said cooling unit decreases when the evaporation of the liquid refrigerant in' said one section is inhibited by inhibiting the absorption of heat thereby.

36. In an absorption refrigerating apparatus, an insulated refrigerating compartment, a cooling unit in said ducting an inert gas to and from said cooling unit, means for supplying a refrigerant liquid to said cooling unit, said cooling unit being so arranged in said compartment that air to be cooled will now thereby in heat transfer relationship but out of contact with inert gas and liquid refrigerant in said cooling unit, and means constructed and arranged to govern the flow of air cluding means constructed and arranged to gov-- ern the circulation of air in contact with one of compartment, means for conrefrigerant liquid to said cooling unit, the arrangement being such that the inert gas and refrigerant liquid flow in opposite directions through said cooling unit, and means for forcing the liquid refrigerant to evaporate into the inert gas in said sections of said evaporator at a selected temperature level including structure for inhibiting absorption of heat by the section first to receive the refrigerant liquid whereby the temperature of said first section drops and liquid refrigerant flows therethrough into the section first to receive inert gas.

39. Absorption refrigerating apparatus comprising aninsulated cabinet including a refrigerating and storage chamber, a refrigerating mechanism associated'with said cabinet including an evaporator having an air cooling part and a chilling part positioned within said chamber, anabsorber connected to said evaporator for circulation of inert gas therebetween, means for supplying refrigerant liquid to said evaporator, and means to control the evaporation of refrigerant liquid into the inert gas in said air cooling part of said evaporator including means arranged to control the abstraction of heat therefrom to govern the quantity of refrigerant liquid which flows through the air cooling part of said evaporator into the chilling part thereof whereby to control the cooling'effect produced by said chilling part.

40. In a refrigerating apparatus, a cabinet structure including an insulated storage chamber, a cooling unit positioned in said storage chamber, said cooling unit including an air cooling section and a chilling section, means for circulating an inert gas through said cooling unit, and means for supplying refrigerant liquid to said cooling unit, the arrangement being such that the inert gas and refrigerant liquid flow in opposite directions through said cooling unit, structure for varying the operating temperature of said chilling unit including structure arranged to promote or restrict evaporation of refrigerant liquid into the inert gas in said air cooling unit whereby the temperature of said chilling unit rises when the evaporation of refrigerant into the inert gas in said air cooling unit is promoted and the temperature of said chilling unit drops when evaporation of refrigerant liquid into the inert gas in said air cooling unit is inhibited.

41. Absorption refrigerating apparatus comprising aninsulated cabinet including a refrigerating and storage chamber; a cooling 'unit positioned in said chamber to refrigerate the air therein, said cooling unit including an air cooling part and a chilling part, meansfor conducting an inert gas to and from said cooling unit,

means for supplying liquidrefrigerant to said,

cooling unit, and means for controlling the production of refrigerant in said parts of saidcooling unit including means arranged to-govem the absorption of heat therefrom.

42. That method of controlling the production of refrigeration in an evaporator positi ned in refrigerating storage chamber to be contacted by air flowing in contact therethrough which includes the steps of flowing an inert gas through said evaporator, supplying a refrigerant liquid to said evaporator, and controlling the temperature at which the refrigerant liquid evaporates into the inert gas by controlling the flow of air in heat transfer relationship with said cooling unit.

43. A refrigerating system including an evaporator having a plurality of parts, means for supplying a refrigerant liquid to said evaporator, means for substantially isolating one of said parts thermally for preventing the absorption of heat and the production of. refrigeration by evaporation of the liquid refrigerant therein, and thermostatic means for controlling said isolating means.

44. Ice making apparatus comprising a water container, a cooling unit arranged to refrigerate the contents of said container in a manner to freeze an ice block therein when said cooling unit is operative and to allow a previously frozen ice block to float to the surface of the water in said tank when said cooling unit is inoperative, a-generating assembly, means for heating said generating assembly to expel refrigerant vapor therefrom, means'for condensing refrigerant vapor expelled from said generating assembly and for supplying the liquefied refrigerant to said cool- .ing unit, and control means constructed and arranged to govern said apparatus to supply liquid I refrigerant to said cooling unit to produce refrigeration therein until an'ice block has been formed'in the water in said tank and to prevent substantial supply of refrigerant liquid to said cooling unit after formation of said ice block until said ice block has floated to the surface of the water in said tank.

45. Absorption refrigerating apparatus comprising an evaporator, a container for water arranged in heat transfer relationship with said evaporator, a generator, a condenser connected to receive refrigerant vapor from said generator.

and to supply refrigerant liquid to said evaporator, means for heating said generator, control means responsive to the thermal condition of said evaporator arranged to govern the energization of said heating means and to condition said apparatus for producing refrigeration for a period of time suificient to produce an ice block and thereafter to condition said apparatus to discontinue production of refrigeration to permit said ice block to float to the surface of the water in said container.

46. In a refrigerating mechanism, a container of water, an evaporator arranged in heat transfer relationship with'a small area of said container to freeze an ice block therein of a size small with respect to the volume of said container, heat operated means for producing refrigerant vapor, means for receiving refrigerant vapor from said heat operated means and for supplying refrigerant liquid to said evaporator, and means controlling said apparatus to supply refrigerant liquid to said evaporator to freeze an ice block in said container and for preventing the supply of re frigerant liquid to said evaporator after the for mation of said ice block to allow said ice block to float freely to the surface of the water in said container. l

47. In a refrigerating mechanism, a container of water, an evaporator arranged to refrigerate a plurality of small spaced areas of the wall of said container beneath the surface of the water therein to produce a plurality of separate blocks of ice in said container, heat operated means for producing refrigerant vapor, means for receiving refrigerant vapor from said heat operated means and for supplying refrigerant liquid to said evaporator, and thermostatic control means arranged to respond to the thermal condition of said evaporator constructed and arranged to govern said apparatus to supply liquid refrigerant to said evaporator to produce ice blocks in the water in said container and to prevent the supply of refrigerant liquid to said evaporator after the formation of said ice blocks to allow said ice blocks to free themselves from the wall of said container and to float to the surface of the water of said container.,

48. That improvement in the art of absorption refrigeration which includes the steps of applying heat to a refrigerant absorbed in an absorbing body to liberate refrigerant in vapor phase, conducting the said refrigerant vapor into heat exchange relationship with cooling air to convert the refrigerant vapor to the liquid state, evaporating said refrigerant in the liquid state in heat transfer relationship with one side of a heat conducting wall which isin heat transfer relationship with a body of water to be frozen below the surface thereof, and intermittently discontinuing the evaporation of liquid refrigerant in heat transfer relationship with said heat conducting wall for periods of time sufficient to allow previously frozen ice to melt out of heat transfer relationship with said heat conducting wall and to float to the surface of said body of Water.

49. In a domestic refrigerating apparatus, a cabinet structure including an insulated refrigerating chamber, an chamber, a container of water in said chamber arranged in heat transfer relationship with said container at a plurality of points beneath the surface of the water therein, a heat operated refrigerant generator, an air cooled condenser, means for heating said generator, means for conducting refrigerant vapor from said generator to said condenser, means for conducting refrigerant liquid from said condenser to said evaporator, and thermostatic control mechanism arranged to govern said apparatus to supply liquid refrigerant to said evaporator for a period of time sufficient to freeze blocks of ice in said container at said points in heat transfer relationship with said evaporator and thereafter to govern said apparatus to discontinue the supply of liquid refrigerant to said evaporator until previously formed ice blocks have melted free of said points and have floated to the surface of the water in said container.

CURTIS C. COONS.

evaporator positioned in said 

